CHRONIC STRESS EFFECTS ON SEXUAL-BEHAVIOR IN MALE AND FEMALE RATS - MEDIATION BY 5-HT2A RECEPTORS

The effects of chronic psychosocial stress on sexual behavior and on t he serotonergic type 2A (5-HT2A) receptor-mediated behavior ''wet dog shakes'' (WDS) were investigated in male and female rats. In Experimen t 1, both bilaterally adrenalectomized and sham-adrenalectomized femal e rats were assigned to either a psychosocial stress condition or a co ntrol condition for 62 days. On the 63rd day, estrogen-primed females were compared on measures of sexual behavior and WDS. Immediately afte r the behavioral tests, the same rats were primed with a subthreshold level of progesterone. Three hours after the administration of progest erone, rats were again scored for sexual behavior and WDS. Psychosocia l stress was found to facilitate sexual behavior and increase WDS in s ham-adrenalectomized female rats providing they were primed with both estrogen and progesterone. In Experiment 2, intact male rats were assi gned to either the psychosocial stress condition or the central condit ion for 30 days. On the 31st day, males were compared on measures of s exual behavior and WDS. No significant differences were revealed on th e spontaneous expression of sexual behavior and WDS. Subsequently, mal es were retested following the administration of the 5-HT2A agonist, D OI. Psychosocial stress resulted in a significant decrease in male sex ual behavior and a concurrent increase in WDS, following the administr ation of DOI. Taken together, these results suggest that chronic psych osocial stress facilitates female sexual behavior and inhibits male se xual behavior, and that the effects of stress on sexual behavior may b e mediated by 5-HT2A receptor activity. (C) 1998 Elsevier Science Inc.